<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>testcssPage</title>
    <style>
        /*css绘制圆，(width==height)&&(border-radius :50%;)*/
        .circle{
            width:100px;
            height:100px;
            background-color: cyan;
            border-radius: 50%;
            -moz-border-radius: 50%;
            -webkit-border-radius: 50%;

        }
        /*css绘制三角形
        width,height ==0,
        预绘制【deriction 】方向的三角形
        控制border-【deriction 相反】的颜色
        border-【deriction 相反】:【px】 【solid】 【color】;
        border-【other】:【px】 【solid】 transparent;
        注：css属性定义为:transparent。意思就是背景透明
        实际上background默认的颜色就是透明的属性。所以写和不写都是一样的*/
        .triangel-all{
            width:0;
            height:0;
            border-top:30px solid cyan;
            border-left:30px solid green;
            border-right:30px solid yellow;
            border-bottom:30px solid pink;
        }
        .triangel-up{
            width:0;
            height:0;
            border-left:30px solid transparent;
            border-right:30px solid transparent;
            border-bottom:30px solid pink;
        }
        .triangle-up2 {
            width:0;
            height:0;
            border:30px solid transparent;
            border-bottom-color:#fff;
        }
        .triangle-down {
            width:0;
            height:0;
            border-left:20px solid transparent;
            border-right:20px solid transparent;
            border-top:20px solid #0066cc;
        }
        .triangle-left {
            width:0;
            height:0;
            border-top:30px solid transparent;
            border-bottom:30px solid transparent;
            border-right:30px solid yellow;
        }
        .triangle-right {
            width:0;
            height:0;
            border-top:50px solid transparent;
            border-bottom: 50px solid transparent;
            border-left: 50px solid green;
        }
    </style>
</head>
<body>
<div class="circle"></div>
<div class="triangel-all"></div>
<div class="triangel-up"></div>
<div class="triangel-up2"></div>
<div class="triangle-down"></div>
<div class="triangle-left"></div>
<div class="triangle-right"></div>

</body>
</html>